In many areas of electronics, in particular entertainment electronics and automotive electronics, optical detection devices are increasingly being used. Examples of optical detection devices are camera devices which are used to record and further process optical still images or moving images of a very wide variety of situations. In particular small format camera devices with CCD sensors or CMOS sensors are becoming increasingly important because they are inexpensive, do not take up much space and accordingly are versatile in their use. Such camera devices are used, for example, in mobile telephones (smart phones), laptops, tablet computers, but also in stand-alone camera systems (e.g. in compact digital cameras). Such camera devices are used in particular in automotive electronics, for example in order to capture images of the road or to allow occupants of the vehicle to make video calls or to take photographs of themselves or of the surroundings. Further examples of optical detection devices are devices with ambient light sensors (ALS), which are used to detect the brightness of the surroundings.
Optical detection devices generally have a light inlet opening of a specific diameter (aperture). The light which passes through the light inlet opening (optionally focused by a lens or lens group) strikes the optical sensor. The optical sensor converts the incident light into electrical signals for further evaluation by an evaluation unit. Such optical detection devices are often arranged behind a light inlet opening of a surface that is otherwise opaque to light. The surface that is opaque to light can be, for example, the frame of a liquid crystal display device of a mobile telephone, of a laptop computer or of a tablet computer. The surface that is opaque to light can further be a (plastics) paneling of a motor vehicle.
In order to arrange a camera device behind the surface that is opaque to light, a (mostly circular or square) opening must be provided in the surface that is opaque to light, which opening does not impair the visual appearance of the otherwise visually homogeneous surface. It is often not desirable to incorporate the camera device into the design (for example of a display frame) as a visible element. A further problem is that a camera which is visible to an observer can also record images of the observer unnoticed, which is often undesirable for reasons of safety and privacy. In order to eliminate the above-mentioned problems, mechanical shutters are known from the prior art which can either be slid in front of the camera device by hand or are electronically actuatable so that they either close or open the light inlet opening for the camera device.
Furthermore, some (mostly higher quality) camera devices have an optical diaphragm (iris) for influencing the amount of light that is incident upon the sensor. The brightness of a recorded image can thus be controlled by a combination of the diaphragm opening and an exposure time. The diaphragm is also used to regulate a degree of depth of focus of the recorded image or to produce a bokeh effect. Such diaphragms are generally formed mechanically from individual blades and are accordingly expensive and susceptible to vibration. Owing to the relatively high outlay for their manufacture, their overall size and their price, such mechanical diaphragms are rarely used in less expensive or more compact camera devices.